Eli5: There’s this Immunologist at Stanford suggesting the possible existence of a shadow biosphere. What is that though?

Question

Eli5: There’s this Immunologist at Stanford suggesting the possible existence of a shadow biosphere. What is that though?

In: 84

Answer 1

Essentially, that there could be a tree of life which is completely separate from the one we know about, living unseen and unnoticed on Earth. We aren’t talking about large or even macroscopic plants and animals, just single celled organisms living pretty much everywhere.

We wouldn’t notice these organisms exist because we don’t really know what to look for, they would potentially have a different chemistry compared to normal life, but there’s billions of single celled organisms basically everywhere. The way we meaningfully research populations of single celled organisms is by looking at their biochemistry, we might just be looking at the wrong things.

It’s an exciting idea because it would mean that life began on earth multiple times, which has important implications on things like the search for life off of earth. It’s generally believed to be not very likely though, simply because it’s likely one set of biochemistry is going to be more efficient than another, over long time frames we would expect the less efficient chemistry to be outcompeted and eliminated.

Answer 2

Essentially, that there could be a tree of life which is completely separate from the one we know about, living unseen and unnoticed on Earth. We aren’t talking about large or even macroscopic plants and animals, just single celled organisms living pretty much everywhere.

We wouldn’t notice these organisms exist because we don’t really know what to look for, they would potentially have a different chemistry compared to normal life, but there’s billions of single celled organisms basically everywhere. The way we meaningfully research populations of single celled organisms is by looking at their biochemistry, we might just be looking at the wrong things.

It’s an exciting idea because it would mean that life began on earth multiple times, which has important implications on things like the search for life off of earth. It’s generally believed to be not very likely though, simply because it’s likely one set of biochemistry is going to be more efficient than another, over long time frames we would expect the less efficient chemistry to be outcompeted and eliminated.